Stringed musical instrument



Jan. 3, 1933. BAKER 1,893,264

STRINGED MUSICAL INSTRUMENT I Filed June 11, 1952 2 Sheets-Sheet l Inventor Jan. 3, 1933. E. F. BAKER STRINGED MUSICAL INSTRUMENT 2 Sheets-Sheet 2 Filed June 11, 1932 000000000 W Fw W N ,Q i MN w Patented Jan. 3, 1933 UNITED STATES PATENT OFFICE EDWARD F. BAKER, OF SHEPHERDSTOWN, PENNSYLVANIA s'rmivonn MUSICAL INSTRUMENT Application filed June 11 1932. Serial No.'616,708.

This invention relates' to an improved stringed musical instrument and has more particular reference to a new type mandolin.

In carrying the inventive conception into 5 actual practice, I have discovered a unique body construction which allows the use of a fullqlength fretted fingerboard, and in fact' body structure in which the principal novelty is found. The body is regarded as distinctive and characteristic in that it utilizes an unusual frame and dual resonator assembly, .thus providing a structure of rare design and utility in that it permits the development of extraordinary tone volume resplendent with resonance and carrying power.

The essential feature of the invention is Y a characteristlc float1ng' the provision of bridge unit.

More specifically, the so-called floating bridge is in the form of a miniature cantilever device having a double fulcrum arrange- .ment wherein the fulcrum points have posi- 'tive contact with the superposed vibratory resonators in order to provide an unusual support for the bridge unit calculated to transmit the vibrations from the strings to the resonators in a characteristically new J manner in order to produce the aforesaid loud but resonant tone.

Other features of the invention will become more readily apparent from the following description and drawings.

In the drawings:

Figure 1 is a top plan view of a mandolin constructed in accordance with the principles of the invention. 7

Figure 2 is a view in section and elevation showing the detailed assembly of parts more plainly.

Figure 3 is a transverse vertical section on the line 3-3 of Figure 2 with the resonators .in elevation. I l o Figure 4 is a view in section and elevation low sound boxes and disc-like in configurashowing the inner end formation of the neck.

Figure'5 is a detail view showing the adjustable connecting pin for one of the truss members of the bridge carrier;

Figure 6 is a front elevation of the bridge unit per'se. V

Figure 7 is a detail sectional view of the spring anchoring bar.

Referring to the preferred embodiment of the invention as illustrated in the drawings, I

it will be observed in Figure 2 that the neck of the instrument is designated by the numeral 8 and is provided with the usual finger 7 board 9 having customary or conventional frets. Thevibratory strings are denoted by i the numerals 10.

As the title of the invention implies, this is a stringed musical instrument of the type generally'referred to as a mandolin, but the neckis slightly longer than the regulation mandolin, andthis arrangement provides an unobstructed playing area for the performer and in fact, allows the finger board to be lengthenedfor the addition of frets if desired. The actual additional length of the neck is made up in the enlarged inner end portion which is here shown as formed with spaced parallel kerfs or slots, in which the adjacent portions of complemental wooden strips 11' and 12 are mounted. These strips, which are somewhat elliptical in top plan view, are secured together through the medium of spacing elements 13 to define a frame 14;. Obviously the frame is of open-work construction to permit unhampered escape and dissemination of the sound waves.

As before implied, the frame constitutes an important part of the body, which body also includes a. pair of duplicate vertically spaced superposed resonators 15 and 16. The lower resonator 15 is fixedly mounted and the upper resonator 16 removable. More over, the upper resonator 16 is staggered or offset with respect to the underlying resonapiorl'l5 for a purpose to be hereinafter clari- These resonators are in the form of 11015 tion. In fact, as indicated in Figure 3,.this

resonator is made up of inner and outer vibratory wooden shells 17 and 18 telescopicaljects and operates. or any other suitable material and provided 1y fitted together. The opposed diaphragm portions of the shells are of concavo convex 1 form to provide the desired bellied form calculated tobetter serve as a onator.

The upper resonator 16 is removably boltresponsive resed to the frame and a special bolt arrange ment is provided at the front. As seen in Figure 2, this particularbolt-is distinguished by the numeral 19 and provided with a thumb wheel 20 for conveniently operating it, the

thumb wheel extending from the rim of the resonator in a position for convenient manipulation. V r

The threaded end of the .bolt is threaded into a hole in a saddle 21 which as seen in Figure 4 is supported from the furcations T22 on-the inner bifurcatedends of the neck.

This bifurcated arrangement comprises a sort'of a yoke which also'support's the string anchoring bar 23. As seen in Figure 7, this is a simple hook to which the adjacent looped "ends of the string are detachab-ly connected in a well-known manner. 1

- It is through this yoke and in advance of the parts 21 and 23 that the bridge 24 pro- The bridge is of bone with customary seats for'the strings. The bridge however constitutes an integral part of the so-called bridge unit 25. In addition tothe bridge the unit includes a cantilever ':carrier made up of a pair of aluminum apertured truss members 26.

These members are disposed in spaced parallelism and connected together by a reinforcing rod 27 and the outer end portions thereof 'fare inclined upwardly so as to position the bridge in'advance of the anchoring bar. 23. These strings maybe trained thereover.

The horizontal portions of the truss members are disposed between the superposed resonators. It will be observed that the head or diaphragm forming the top of the'lower resonator is provided at the center of its crownportion with a pair of recessed bosses 28 definingbearings, for a pair of short fulcrum pins 29 carried by the central portions of the truss elements or members 26. This provides a central rocking support for the carrier which support'is in vibratory connection with the lower resonator.

' The lower head or diaphragm of the upper resonator 16 is also provided with inlaid bosses 30 recessed as seen in Figure 5 to provide the requisite bearing seat for the threaded end of retaining pins 31. These retaining 'pins'are adjustably mounted in sockets 32,

plvotally connected as at 33 to the adjacent ends of the truss elements to provide a second fulcrum for the bridge carr er. Thus the intermediateportion of the carrier is fulcrumed on the crown portion or belly of the to allow the fingerboard videa'to provide the floating action of the resonator 15 while the rear end portion is fulcrumed on the pin 33 joined to the upper resonator through the medium of the pointed contact pins 31. This is an unusually sensitive arrangement which allows the vibrations of the string to be communicated from the bridge simultaneously to the superposed oil'- set resonators. Incidently the reason for having the top resonator removable is to permit access to be had to the bridge carrier for adjustment of the sensitivity and replacement of parts if necessary.

' By having the string anchoring means and floating bridge .in the .position illustrated in Figure 1, considerable space is provided for placement-of the hand resting platea34'and as before stated there is suflicient space here to be lengthened if desired.

It is believed to be new-in this line of endeavor to provide an open-work frame with the superposed staggered or offset sound.

boxes or resonators and the intervening bridge units possessing the double fulcrum,

bridge 24. Consequently the bridge is indirectly supported by the resonatorsthrough the medium of; alight-weight carrier in the form of a mlniature cantilever unit. Thus this bridge COIIStILlCtlOI'l.itlld'I'GSOIlltOl arrangement is calculated to supply the means necessary for the development of a robust tone having the desirable resonance, quality, and carrying power.

It is thought that the descriotion taken in connection with the drawings will enable a clear understanding of the invention to be had. Therefore, a more lengthy description is thought unnecessary. i

While the preferred embodimentof the into be understood that minor changes coming within the field of invention claimed may be resorted to ifdesired.

I claim: 1. A stringed musical instrumentcomprising abody including upper and lower vibratory sound boxes disposed in spaced parallelism, :a neckattached to the "body and having a fretted fingerboard, string anchoring means carried by said body, a bridge, and means for adjustably connecting said bridge in vibratory relationship with said sound boxes. i f Y 2. 'A stringed musical instrument comprising a body including upper and lower vibravention hasbeen shown and described,'it is i end to one of the sound boxes and fulcrum connection intermediate its ends with the remaining sound box.

3. A stringed musical instrument of the class described comprising a body including an open frame, a neck attached to said frame, string anchoring means mounted on the frame, a stationary resonator mounted beneath the frame, a detachable resonator mounted above the frame in spaced parallelism to said first-named resonator, a bridge, a carrier for said bridge said carrier being interposed between the adjacent faces of the resonators and having adjustable and detachable fulcrum connection with said resonators.

4. A stringed musical instrument comprising a body including a substantially elliptical frame of open-work construction, a fin- 'gerboard equipped neck attached to the frontal portion of said frame, string anchoring means carried by the frame, a hollow disc-like resonator rigidly secured to and underlying said frame, a second hollow resonator detachably secured above the frame, said second-named resonator being disposed in spaced eccentric offset relation with respect to the first-named resonator, a bridge, a pair of spaced parallel truss members attached to said bridge and arranged between the resonators, fulcrum pins carried by the intermediate portions of said truss members and rockably connected with bearings on the central portion of the first-named resonator, and fulcrum pins pivotally connected to the rear ends of said truss members and detachably connected with bearings carried by the central portion of said second-named resonator. 5. A stringed musical instrument comprising a neck, a frame fixedly connected to the inner end of said neck, a pair of spaced vibratory members attached to said frame, a bridge and a carrier for said bridge, said carrier being interposed between said vibratory members and connected at longitudinally spaced points to said members to provide the desired floating bridge effect.

6. A stringed musical instrument comprising a neck, a frame fixedly attached at the inner end of said neck, a pair of spaced substantially parallel vibratory members attached to said frame, a bridge, and a carrier for said bridge disposed between said vibratory members and embodying a pair of spaced parallel interconnected truss elements, said elements being connected at their rear ends to one of said vibratory members and intermediate their ends to the remaining vibratory member.

In testimony whereof I aifix my signature.

EDWARD F. BAKER. 

